Self-steering toy auto



March 12, 1957 Filed June 11, 1954 w. M. SARFF 2,784,527

SELF-STEERING TOY AUTO 2 Sheets-Sheet l INVENTOR. Warren m. Sarff March 12, 1957 w. M. SARFF SELF-STEERING TOY AUTO 2 Shets-Sheet 2 Filed June 11, 1954 v INVENTOR. Warren. m. Sarff WV @M% United States Patent SELF-STEERING TOY AUTO Warren M. Sarff, Kirkwood, Mo.

Application June 11, 1954, Serial No. 436,088

17 Claims. (Cl. 46--202) This invention relates to self-steering toy auto and it comprises a toy auto having the usual auto body, front axle and wheels mounted thereon, a weighted element pivotally mounted inside the auto body in such fashion that it is free to swing about its pivoat under \the action of gravity in a direction transverse to the principal axis of the auto, a vertical pivot mounted at the front of the auto, said front axle being pivotally mounted on said pivot, connecting means between said weighted element and the front axle adapted to turn the front axle in accordance with the transverse movements of said weighted element in such direction that, when the auto is resting on a surface which slopes downwardly, the front axle and wheels are caused to turn automatically in such direction that the auto is directed down hill; all as more fully hereinatfer set forth and as claimed.

This application is a continuation-impart of my copending application, Serial No. 370,309, filed July 27, 1953, and now abandoned. In this prior application I have described and claimed a self-steering toy auto and have described two different modifications of an automatic steering mechanism for said auto. In the present application I describe still another modification which in some respects appears to represent an improvement over the modifications described in the acknowledged application.

Several types of automatic steering devices have been devised for toy autos. Some of these are capable of steering the autos through rather complicated courses. None of these however appears to be capable of directing an auto in a course depending solely upon the slope of the base on which the toy is being driven.

I have discovered a simple and inexpensive steering mechanism which automatically turns the front axle of an auto in such direction that the auto is directed in a down hill direction whenever a slope is encountered in its path. This makes it possible to direct the auto over any desired course on a base merely by tilting the base in the direction in which it is desired to make the auto go. If the auto is self-propelled it is possible for it to follow any desired 7 course so long as the course is properly banked on the curves. An oval or circular course, for example, can be provided with banked turns and the auto will follow the course automatically. Several toy autos can be operated simultaneously on such a course, simulating an Indianap' olis speedway race with the inevitable collisions, breakdowns, repairs, etc. Small fry can be entertained over long periods with such an equipment.

My invention can be described with greater accuracy by reference to the accompanying drawing in which several modifications of my steering mechanism are illustrated more or less diagrammatically.

In this showing,

Fig. 1 is a perspective view of a spring-propelled vehicle equipped with my automatic steering mechanism, the auto body being show-n in outline,

Fig. 2 is a perspective view of a modified steering mechanism which is operated by gears and mounted on a chassis, with the auto body removed,

"ice

Fig. 3 is a bottom view of a toy auto equipped with another modification of my automatic steering mechamsm,

Fig. 4 is a side view partly in vertical cross section of the front end of the modification of Fig. 3, taken along the line 44 of Fig. 3,

Fig. 5 is a perspective view of an oval base or tray mounted on a central pedestal for tilting purposes, the

tray being provided with a banked peripheral track for my toy auto and showing such a toy on the track.

Fig. 6 is a vertical sectional view of the tray taken along the line 6-6 of Fig. 5 and showing the banking of the track,

Fig. 7 is a pantial perspective view of the rear end of one of my toy autos equipped with a battery drive, one of the wheels being removed for clarity of presentation, while Fig. 8 is a perspective view of a device for adjusting the position of the front axle with respect to the chassis of the auto and thereby adjusting the steering mechanism.

In the various figures like parts are designated by like reference numerals. In making my toy auto it is most convenient to make the auto body, shown generally at 1 (Fig. l), removable from the chassis, shown generally at 2. The latter is formed with a base plate 3 on which are mounted the wheels 40 and the operating mechanism.

The automatic steering mechanism shown in Fig. l comprises a two-armed lever, shown generally at 4, mounted approximately at its center on a pivot 5 which is secured to the base plate. At its rear end this lever is provided with a vertical slot 6. Mounted directly above this slot is a pendulum 7, the mounting 8 of this pendulum being attached to the body of the auto at any convenient point inside the top. An operating rod or pin 9 depends from the bottom of the pendulum and this pin is received in the slot 6 of lever 4. If the pendulum is caused to swing laterally by a tilt in the road this causes the lever 4 to oscillate about its pivot 5. At its front end lever 4 is bifurcated and a vertical pin 10 is mounted between the bifurcations. The position of this pin is adjustable, several holes 11 being provided in the bifurcations of the lever 4 for adjustment purposes. The front axle 12 is pivotally mounted on a vertical pivot 13 mounted on the base plate. This pivot is also adjustable in position along the base plate, holes 11a being provided for this purpose. A forked lever 14 is either secured do or made integral with the front axle and the vertical pin 10 of lever 4 operates within the slot 15 formed in the rear end of lever 14.

It is believed evident from the construction described that the front axle and wheels of the auto arm forced to turn by any transverse movements of the pendulum. If the auto encounters a banked turn to the right, for example, the pendulum swings to the right and this causes the front axle to swing in clockwise direction. The auto thus automatically follows a curving path provided that r the turns are properly banked and provided that the position of the pin 10 and pivot 12 are properly adjusted.

A conventional spring drive is shown for the auto of Fig. 1. This drive comprises a spiral spring 16 mounted on the rear axle 17, one end of the spring being secured to the axle adjacent spur gear 18 and the other to the right rear wheel 19. The winding mechanism comprises a second spur gear 20, meshing with gear 18 and mounted on a shaft 21. One end 22 of the shaft is square and a key 23 is provided to wind the mechanism. A conventional dog 24 is provided to prevent shaft 21 from spinning when the key is removed. All this driving mechanism can be conveniently mounted on the base plate 2 to form part of the chassis.

The body part of the auto may be secured to the chassis in any suitable manner. At the front the chassis can be hinged to the front bumper of the body, as at 25, for example, while spring clips 26 can be used at the sides and/or the rear to hold the body to the base plate of the chassis. When the body is mounted on the chassis in this fashion it can be swung upwardly about its front hinge thus exposing the entire driving and steering mechanisms. The pendulum lifts with the body and'when the body is replaced it is only necessary to be certain that the depending operating pin 9 of the pendulum enters the slot 6 in lever 4 before snapping the body into position on the chassis.

In Fig. 2 the chassis of a modification is shown in which the means connecting the pendulum with the front axlecomprises a shaft 27 mounted in lugs above the base plate and having a gear 28 at its rear end. The pendulum in this modification consists of a gear section 7a whose teeth 29 mesh with the gear 28. The pendulum is weighted at 30 and pivotally supported at 31 for transverse pivotal movement in mounting 8a, the latter being mounted inside the top of the body. At its front end shaft 27 is provided with bevel gear 32 which meshes with bevel gear section 33, the latter being mounted on the front axle 12a. The axle and gear section oscillate about vertical pivot 130. In this construction, as in the case of the steering mechanism ofFig. 1, when the roadway is banked, the pendulum 7a causes the front axle and wheels to turn in the proper direction to follow the roadway. Three spring clips .26 are provided on the base plate of this modification so that the body can be snapped in place.

In Figs. 3 and 4 a modification is shown in which all parts are mounted inside a plastic auto body 1a, no chassis being required, which represents an important simplification. The front axle 12b is mounted on vertical pivot 13b as before but this pivot depends from a pedestal 60 (Fig. 4) which is secured under the hood of the auto body. The rear axle 21b is merely a spindle mounted in plastic lugs 71 inside the'auto body at the rear with the rear wheels rotatably mounted on the spindle. The weighted element 7b, which takes the place of the pendulum used in the other modifications, is mounted on the front end of a transverse lever 61, the latter being secured to or being integral with the axle. For best'results pivot point 1312 should be slightly to the rear of the line of centers of the wheels, i. e. to the rear of the shaft 63 on which the wheels are mounted, as shownin Fig. 4. This causes the weight of the front end of the auto body to be applied to the lever 61 to the rear of the fulcrum or pivot point of the lever. The weight 711 is applied to the front arm of the lever on the opposite side of the fulcrum and, for best results the weight should be atleast sufficient to counterbalance the weight of the auto body on the lever. Thus I have found that when the lever dips downwardly at its front end it is somewhat more responsive to changes in the slope of the roadway. It then functions much like a pendulum, as in the other models. For best results it is also advantageous to have the front wheels toe inwardly to a slight extent, for example so they are on the circumference of a circle with the pivot point 13]) at its center, as shown in Fig. 3.

In order to prevent the front axle of this model from rotating too far, I provide a vane or tail 62 which extends rearwardly from the rear end of the lever arm and is sufficiently long to engage the body of the auto when the front axle has been rotated through an angle of approximately 45 from its center position. This angle can, of course, be varied from about 25 to 60 or more.

In operation the weight 71) tends to turn the front axle until the lever points in the direction of the. slope of the roadway, i. e. so it points directly down hill. If the auto is not already traveling in this direction the front wheels soon steer it so that it does go down hill. The auto will respond to a very slight banking of the roadway. The steering system is so sensitive that the weight 7b of this model can be made smaller than the weights of the pendulums in the other two models. The model of Figs. 3 and 4 is more simple and can be made at a lower cost.

In Fig. 5 a banked trackway 34 is shown as part of a board or tray 35. The tray is dished as shown at 36 in Fig. 6 to provide the proper banking around the oval track. The tray is provided with a central pivot or pedestal 37 at the bottom so that it can be readily tilted, if desired. This pivot can be removed when the toy auto 57 is self propelled. But it is possible, of course, to tilt the tray by hand in order to propel the auto. With a little practice it is possible to make an auto circle the track merely by tilting the tray about a transverse horizontal axis, relying upon the banking at the turns to cause the wheels to turn properly to make the curves. If two or more self-propelled autos are available it is more fun to remove the pivot and to start the autos running together either abreast or one behind the other to see which will make the most-turns before stopping or having an accident.

In Fig. 7 another modification of a propelling mechanism is shown. This is mounted on the base plate between the two rear wheels, one of which ttla is driven by the mechanism. A flashlight battery 33 is mounted between two spring clips 39 at either side. At one end the battery is grounded to the base plate by spring contact 40', while the other end makes contact with a spring connector 4l which is mounted on an insulated plate 42. A midget motor 43 is also mounted on the plate and one terminal 44 of the motor is grounded to the base plate while the other 45 is electrically connected with connector 41 through a switch 46. The switch is mounted from below on plate 42 and can be operated by handle 47 which protrudes beneath the base plate. The operating shaft 48 of the motor drives spur gear 49 which meshes with gear 50, the latter being keyed to the rear axle 50. At least one of the rear wheels must be keyed to the axle but the other can be left free if desired.

A driving mechanism of the type shown in Fig. 7 is capable of running one of my autos for several hours, and if two or more autos having similar equipment are available, a prolonged race can be staged on a properly banked track. The cars can be distinguished by having dilferent colors. Suitable rules can be provided. For example, a 5 second delay can be required after a car stalls or runs off the track before it can be started again, the players can be permitted to oil their cars during the race or to make repairs. Penalties can be provided for cars which collide with others etc.

If desired a board can be provided with simulated streets, houses, garages etc. If such a board is provided with a central pivot it is possible to tilt the board and thereby to drive the auto along the streets, making turns where desired, parking and even hacking into a garage, if desired. A considerable amount of skill can be acquired in the handling of such a device.

In constructing my automatic steering mechanism for cheaper models which are not provided with self propulsion, it is only necessary that the front axle be turned by the weighted element in the direction of the slope of the base, the exact angle through which it is turned being more or less immaterial. However, in the case of self propelled autos designed to operate on a base provided with banked turns, the degree of banking at the turns and the radius of curvature of the turns should be roughly correlated with the angle through which the front axle turns when the auto enters the turn. Otherwise the auto may not stay on the track. For example, if the car is headed due north and enters a banked curve sloping to the east at an angle of 15 from the horizontal and the steering mechanism is adjusted so that the front axle turns through the same angle that the slope of the base makes with the horizontal plane when the longitudinal axis of the auto stands at right angles to theslope of the base,

the axle will turn through an angle of clockwise. Obviously the radius of curvature of the curve must be roughly correlated with the wheel base of the auto in order that the auto will stay approximately in the same position on the roadway as it rounds the curve.

In order to provide a rough guide as to these factors I might state that, when the steering mechanism is adjusted to turn the front axle through the same angle as the base makes with the horizontal plane and when the wheel base of the car is A the radius of curvature of the banked curves, the average slope along the curves should be a approximately 15 from the horizontal; when the wheel base of the car is /8 the radius of curvature of the curves, the slope along the curves should average about from the horizontal; when the wheel base is /2 the radius of the curves, the average slope along the curves should be about from the horizontal, and when the wheel base is equal to the radius of curvature of the curves, the banking of the curves should be about 45 from the horizontal.

When the steering mechanism is so constructed and arranged that the front axle is caused by the action of the weighted element to turn through an angle which equals that of the base with respect to the horizontal plane when the auto stands at right angles to the slope of the base, the steering can be said to be fully or 100% compensated. I have found that best results are obtained by constructing the steering mechanism so that the compensation obtained is from about 90 to 180% compensated. The higher compensations are best for the cars not equipped with self propulsion, whereas in the case of the autos designed to run on a banked track the compensations should preferably be within the range of from about 90 to 130%. Of course these relationships hold for only relatively small angles not exceeding 45 since the maximum pivoting angle of the front axle is about 45".

For best results it is advantageous to have the steering mechanisms of the models shown in Figs. 1 and 2 adjustable as to their compensations. Two such adjustments for this purpose are shown in Fig. 1 wherein the spaced holes 11 provide adjustment for the pivot 10 while the spaced holes 11a provide adjustment for the pivot 13. A still more accurate adjustment means is shown in the partial view of Fig. 8 wherein the front axle 12a is pivoted at 13a on top of a sliding block 51 which is provided with a key-way 52. i The base plate 3a is provided with a slot 53 which fits the key-way. The block is threaded to receive an adjusting screw 54 which is provided with a knurled head 55. The screw is swiveled at its rear end in a lug 56 which is secured to the base plate. This adjusting mechanism is adapted to be used in connection with the forked lever 14 of Fig. 1, this lever being mounted on top of the axle 12a, and with the lever 4 of Fig. 1. It is believed evident that, as the block 51 slides on the base plate as the screw 54 is turned, this will change the relative positions of the pivot 13a and the pin 10 of lever 4 (Fig. 1), thereby adjusting the angle through which axle 12a will turn for a given angular displacement of lever 4 caused by the pendulum.

The model shown in Figs. 3 and 4 requires no adjustment for its steering mechanism since in this model the weight 7b always tends to turn the front wheels so they will point directly down hill. It is remarkable how quickly this model will follow changes in the slope of the base on which it rests. It will follow hair pin curves as well as gradual curves and, if operated on a tray of the type shown in Figs. 5 and 6, it will tend to keep close to the lower edges of the banked turns.

While I have described what I consider to be the best embodiments of my invention, it is obvious, of course, that various modifications can be made in the specific structures and mechanisms which have been described without departing from the purview of this invention. Thus while I have described three types of automatic steering mechanisms operated by a weighted element, it is evident that this weighted element can be replaced by any type of equivalent weight-shifting mechanism which operates by gravity and is capable of doing sufficient work to turn the axle of the toy auto. Any type of propulsion means can be used, such as jet motors or the type of motor used in remote-control toy autos. Any suitable system of gears and/or levers can be used to transmit the motions of the weighted element to the front axle. And any construction material can be used, such as metal or plastic or a combination of these materials. It is advantageous, of course, to construct the weighted element of lead owing to its high specific gravity. Further modifications of my invention which fall within the scope of the following claims will be immediately evident to those skilled in this art.

What I claim is:

1. A self-steering toy auto having the usual auto body, front axle and wheels mounted thereon, a weighted element mounted inside the auto body and free to move under the action of gravity in a direction transverse to the longitudinal axis of the auto, a vertical pivot mounted at the forward end of the auto, said front axle being pivotally mounted on said pivot, connecting means mounted between saidweighted element and the front axle adapted to pivot the axle and wheels in proportion to the transverse movements of the weighted element; said connecting means being so constructed and arranged that the axle and wheels are pivoted to direct the auto down hill when the base on which it rests slopes with respect to the horizontal plane and when the auto is pointed in a direction other than down hill.

2. The toy auto of claim 1 wherein said connecting means are constructed to pivot the front axle through an angle within the range of from about to of the angle between the slope of the base and the horizontal plane when the longitudinal axis of the auto is at right angles to the direction of the slope of the base; this relationship holding for small pivoting angles within the range of from about 0 to 45.

3. The toy auto of claim 1 wherein said connecting means comprises a vertical pivot mounted between the weighted element and the front axle, a lever pivotally mounted on said vertical pivot, a vertical slot at the rear end of said lever, a pin depending from said weighted element and adapted to engage said vertical slot, 21 second lever secured to said front axle, a vertical slot at the rear end of said second lever, a vertical pin at the forward end of said first lever adapted to engage the vertical slot of said second lever in such fashion that, when the first lever is pivoted by the pin of the weighted element acting in its slot, the second lever is pivoted correspondingly, thereby turning the axis of the auto in proportion to the transverse movements of the weighted element.

4. The toy auto of claim 1 wherein said connecting means comprises a horizontal shaft rotatably mounted between said weighted element and the front axle, a depending gear section mounted on said weighted element, a gear mounted on the rear end of said shaft adapted to engage with said gear section, a second gear section mounted on said front axle, a gear mounted on the forward end of said shaft and adapted to engage said second gear section; said elements being so constructed and arranged that an angular transverse movement of said weighted element causes its depending gear section to rotate said shaft thereby turning the front axle through an angle proportional to the angular -motion of the weighted element.

5. The toy auto of claim 1 comprising an auto top and chassis, the weighted element being mounted inside the auto top while the axles, wheels and connecting means are mounted and form part of said chassis, the top being removable from the chassis.

6. The toy auto of claim 1 wherein the auto is provided with a self propelling means.

7. A self-propelled, self-steering toy auto having the *1 a usual auto body and chassis with front axle and wheels mounted thereon, a pendulum suspended from anupper part of the body in such manner that it is free. to oscillate in a transverse plane, connecting means mounted on the chassis between the pendulum and the'front axle for turning the front axle, means mounted on the pendulum for operating the connecting means in such fashion that the front axle is turned through an angle proportional to the angle between the slope of the base on which the auto rests and the horizontal plane when thelongitudinal axis of the auto is at right angles to the direction of the slope of the base so that the auto tends to be steered in a down hill direction, and means for propelling the auto.

8. A self-steering toy auto having the usual auto body, front axle and wheels mounted thereon, a weighted element pivotally mounted inside the auto body in such fashion that it is free to swing about its pivot under the action of gravity in a direction transverse to the principal axis of the auto, a vertical pivot mounted at the front of the auto, said front axle being pivotally mounted on said pivot, connecting means betweensaid weighted element and the front axle adapted to turn the front axle in accordance with the transverse movements of said weighted element in such direction that, when the auto is resting on a surface which slopes downwardly, the front axle and wheels are caused to turn automatically in such direction that the auto is directed down hill.

9. The toy auto of claim 8 wherein the weighted element is mounted in front of the front axle on the fore end of a lever which is mounted transversely on the front axle.

10. The toy auto of claim 8 wherein the said vertical pivot is mounted on and depends from the body of the auto so that the weight of the front end of the auto rests on the front axle at its pivot point.

11. The toy auto of claim 10 wherein the weighted element is mounted in front of the front axle on a lever mounted transversely on said front axle, wherein the weight of the front end of the auto rests on the front axle and on the lever at a point slightly to the rear of the line joining the centers of the wheels, the weight of the weighted element being at least sufficient to counterbalance the weight of the auto so that the front end of the lever tends to dip downwardly due to the weight of the weighted element.

12. A self-steering toy auto comprising an auto body, a rear axle mounted inside the body at the rear, a vertical pivot mounted inside the auto body at its front end, a front axle rotatably mounted on said vertical pivot, a substantially horizontal lever transversely mounted on said front axle, and a weight mounted on the front end of said lever in front of the front axle in such manner that when the auto is resting on a base'which slopes in a direction transverse to the principal axis of the auto the weight tends to turn the front axle in such direction that the auto will run down the slope.

13. The toy auto of claim 12 wherein means are provided to prevent the front axle from turning through an angle of substantially more than 45 from its central position.

14. The toy auto of claim 13' wherein said means comprises a vane mounted on the rear end of said'lever and extending to the rear inside the auto body in such fashion that when the front axle is rotated from its central position through an angle of about 45 further rotation of the axle is prevented by the vane engaging the body of the auto.

15. The toy auto of claim 12 wherein the Weight of the front end of the auto body rests on the front axle at its pivot point and wherein said pivot point is slightly to the rear of the line connecting the centers of the front wheels.

16. The toy auto of claim 15 wherein the weight of the front end of the auto is counterbalanced by the weight mounted on the lever so that the front end of the lever tends to dip downwardly.

17. A self-steering toy auto comprising a plastic auto body, a rear axle provided with wheels mounted inside the plastic body at the rear, a pedestal mounted inside the auto body at its front end, a vertical pivot depending from said pedestal, a front axle rotatably mounted on said vertical pivot, front wheels mounted on said axle and toed inwardly, a substantially horizontal lever transversely mounted on said front axle, the said vertical pivot passing through said lever at a point to the rear of the line passing through the centers of the front wheels so that the weight of the front end of the auto body rests on the rear end of the lever, and a Weight mounted on the front end of said lever in front of the front axle sufficiently heavy to counterbalance the weight of the auto body on said lever and to cause the front end of the lever to dip downwardly so that, when the toy auto is resting on a surface which slopes in a direction transverse to the principal axis of the auto, the weight tends to turn the front axle and wheels in such direction that the wheels point directly down hill.

References Cited in the file of this patent UNITED STATES PATENTS 1,661,864 Zabel Mar. 6, 1928 2,004,915 Clark June 11, 1935 2,216,497 McHenry Oct. 1, 1940 2,386,745 Yarbrough Oct. 9, 1945 2,388,629 Anderson Nov. 6, 1945 2,454,598 Doyle Nov. 23, 1943 2,501,206 Brackett Mar. 21, 1950 2,585,754 Dunkelberger Feb. 12, 1952 2,642,700 Simmer June 23, 1953 2,651,882 Core Sept. 15, 1953 

